If you have ever received an inspiring message inside of your 40th birthday card, now is the time to share it with NASA.

Voyager 1, which has become the longest continuously operating space mission ever, as well as the most distant manmade object, is celebrating 40 years of space exploration. Over the course of its trajectory, it has become the first spacecraft to enter interstellar space and the only spacecraft to fly by Jupiter, Saturn, Uranus and Neptune.

In honor of its birthday, NASA is giving social media users the chance to send in an inspiring message that might be beamed up to Voyager 1 on September 5th.

Only one of the submissions will be elected as the official birthday message for Voyager. The messages can be submitted on Twitter, Facebook, Google+, Tumblr, or Instagram under the tag #MessageToVoyager.